Screen or separator.



T. I. STURTEVANT.

SCREEN 0R sEPARAToR.

APPLICATION FILED MAR. I, I9l3. 1:9119988; Patented June 8, 1915.

3 SHEETS-SHEET I.

ligl.

T. J. STURTEVANT.

SCREEN 0R SEPARATOR.

APPLICATION FILED MAR1 3 SHEETS-SHEET 2.

Patented June 8,

LLQSS ,I mlfefels @Ermes CU fwowJA/THQ. WASWNGTON D A' T. J. STURTEVANT.

SCREEN 0R SEPARATOR.

APPLICATION FILED MAR. I. Isla.

MII

I S. Z H. vw w m 9. n o 113 .wv www T I onw n H 5 DUS n hm Mw t n3 .mw a Y P .,v. l 8 8 9 n' THE NDRRIS PETERS co., PHoTaLIrHo., WASHINGrON. D. C4

THOMAS JOSEPH STURTEVANT, OF WELLESLEY, M'ASSACHUSETTS, ASSIGNOR TO STURTEVANT MILL COMPANY, A CORPORATION OF MAINE.

SCREEN 0R SEPARATOR.

Specification of Letters Patent.

Patented J une 8, 1915.

Application tiled March 1, 1913. Serial No. 751,560.

arator by means of which the screening operation is expeditiously performed. This result is effected by the assistance of a rotary fan adapted to produce reversing or pulsating air currents which will serve to vibrate the wire mesh screen more or less, and which will act alternately to force fine material through rthe screen and to clear the screen, so that the meshes thereof will not become clogged by the material being screened.

The present invention relates more particularly to an improved embodiment of the vinvention set forth in my application No.

740,415, filed Jan. 6, 1913, as will hereinafter more fully appear.

In the accompanying drawings, Figure 1 is a plan View of a screen or separator embodying the present invention, and Fig. 2 is a central vertical section thereof. Fig. 3 is a horizontal section on line 3-3, Fig. 2, and Fig. 4f is a central vertical section of a somewhat diderent embodiment of the invention from that shown in Figs. 2 and 3. Fig. 5 is a horizontal section illustrating another di (ferent form of the invention.

Referring to the drawings, l2 denotes a suitable casing mounted on legs 13. Suitably supported on or within the casing 12 are brackets 14 and 15 which afford bearings for a vertical rotary shaft 16 provided with a pulley 17 by which it may be driven from any suitable source of power. Mounted within the casing l2 is a non-rotating or stationary screen 18 which, as herein shown,

is of cylindrical form and consists 'preferably of fine-mesh wire-cloth which is stretched upon a suitable frame comprising an upper end head 19 and a lower hopper Vpart 20 to receive the tailings from the separator. As herein shown the `bracket 14C is mounted on the upper side of the casing 12 while the bracket l5 is mounted on the hopper part 20. It will be understood, however, that the screen may be of polygonal or other suitable form, and that it may be of fine or coarse mesh, depending on the desired output of the screened material.

Mounted within the screen 18 is a rotary fan made in the form of a drum and comprising upper and lower end heads 21 and a series of wings or blades 22 attached to said end heads and to a central bracing ring 23. rThe said ends heads are provided with hubs 24 which in the form of the invention 'shown in Fig. 4, are attached directly to the shaft 16 provided with a driving pulley 26, while in the form of the invention shown in Fig. 2 one of said hubs is attached to a hollow shaft 25 provided with a driving pulley 26, the other of said end heads being provided with a sleeve 27 which aifords a bearing for one end of the shaft 16. The wings or blades 22 kare. preferably all disposed in one circular plane and are reversely inclined alternately for the purpose of producing alternating or pulsating air currents which will serve to force fine material through said screen as well as to clear the said screen, by pulsating action, so as to prevent the screen from clogging, and will also serve to vibrate the screen 18 more or less.

In the operation of the improved screen or separator the material to be screened will be fed from a hopper 28 onto the upper end head 21 of the rotary drum fan, and will be carried by centrifugal action outward until it can fall down in the spacey between the wings or blades of said fan and the cylindrical screen 18. As the material falls into the space referred to the whirling action of the fan will cause the material to travel spirally, while the pulsating air currents created by the fan will'cause the iine material to be carried through the screen and into the space within the ycasing 12 outside of said screen so that it can fall down into the whopper 29 arranged to receive said fine material, the tailings passing downward into Y ranged Within thelirst-named fan, and comf ward will come in contact with the screen clothing tangentially and the material `Will therefore be screened finer than the mesh of the wire clothing, owing to the inclination of the path of the material to the plane of said screen clothing. Y Y

F or the purpose of modifying or assisting fthe action of the pulsating or alternating air currents created by the rotary pulsating current fan above described, a second cylindrical or drum-form of fan, preferably arprising end heads 30 and radiating Vblades 31, be employed. The end heads() areV provided With hubs 32 attached, as shown'in Fig. 2, to the shaft 16. This second or inner fan, which, asl herein shown, is a noni-pulsating current fan, will, in practice, beV rotated in a direction opposite to the direction of rotation of the outer or pul- V eating vcurrent fan, and will have effect to increase the power of the air pulsations While reducing Vthevelocity of the Whirlwind, action, caused by the pulsating current fan, to any desired extent, so as to prevent excessive Wearof the Wire-cloth screen, In other Words, the inner fan, by causing the pulsating fan to Work in an opposing current, causes theV air to pulsate more strongly. This isy dueto the fact that if the f pulsating fan should move in a Whirlwind of air moving at the same rate and in the Vsame direction as th'efan blades the latter Would not displaceV any air, and therefore would `not .cause any air pulsations. It fol lows, therefore, that inthe use of the double fan design the rate of pulsation of the air Ycan be regulated kby the speed of the pulsating fan, and thevforce of the pulsations can bevaried by the inside fan which controls more or less the speed of the air currents in which the ypulsating fan Works. This secondfan may, however, be arpulsating current fan Vif desired, and this may be found preferable for some kinds of Work. This will be understood from Fig. 5 which `shows a pulsating current fan having alter nating reversely inclined Wings or blades 33 coperating with theV rotating pulsating current fan having reversely inclined Wings or blades Q2 disposed, in this particular Vform Vof the invention, in .alternating groups, as hereinbefore described. The

speed of rotation of the tWo fans, as Well asV their relative speeds, can be regulated to suit any screenable material owing to the fact that these rotary fans are independ-y ently driven by separate pulleys.

The .inventionis not to be understood as being limited to the details herein lshown and described, as such details may be varied Widely, Within the limits of mechanical skill, Without departing from the essence or scope of the invention.

.Having thus described Vmy invention I claim and desire to secure by Letters Patent:

1'. In a separator, the combination With a suitable casing, of a vertically disposed stationary screen Within the saidcasing, a vertically disposed rotating fan karranged ad- .jacent to -said screen and provided With alternating reversely inclinedy bladesall disposed in one'circular plane 'and serving to produce alternating reversing or pulsating air currents, and meansV for supplying to the upper part of the separating means the material to be screened. y

' 2. In a separator, the combination With a suitable casing, of a vertically" disposed stationary screen Within the said casing, a vertically disposed rotating fan arranged adjacent to said screen and provided with alternating reversely inclined blades, for the purpose of producing alternating reversing Y y or pulsating air currents, means for supplying to the upper part of the. separating means the material to be screened, and a second vertically arranged, rotary. fan Within and coperating With the first-named fan and rotatable independently thereof.

3. In a separator, the combination With a suitable casing, of a vertically disposed sta-v tionary screen Within the said casing, a vertically disposed rotating fan 'arrangedk ad-y jacent to said screen .and provided with alternatingreversely inclined blades, for the purpose of producing alternating reversing ory pulsating air currents, means for supplying to the upper part of the separating means the materia-l to be screened, and a non-pulsating current, vertically arranged, t

' rotary fan coperating with the first-named fan and rotatable independently thereof.

1l, In a separator, the combination With a suitable casing, of a vertically disposed stationary screen Within the said casing, a vertically disposed rotating fan arranged adjacent to said screen and provided with alternating reversely inclined blades all disposed in one circular plane and serving to produce alternating reversing or pulsating air currents, means for supplying tothe upper` part of the separating Vmeansthe material to be screened, and means for keeping separate and discharging the tailings and fine material. Y

5. In a separator, the combination with a to be screened, and means for supplying the material to be screened to said centrifugal distributer.

In testimony whereof I afm my signature, in presence of two Witnesses.

THOMAS JOSEPH STURTEVANT.

Witnesses :I

W. F. ELLIS, L. H. STURTEVANT.

Uopies of this patent may be obtained for :five cents each, by addressing the Commissioner of Patenti,

Washington, D. G. 

